Abstract: Based on the physical model and the calculation method proposed in references[1,2] by anthors,a calculation program of XQMA of micre-particle specimens by using Monte Carlo simulation was made.A series of theoretical formulae for the electron scattering and the production, absorption and fluorescence of characteristic X-rays in particles were given.The datum documents are established in the program.The softwa-re has the ability of automatically treating data,and it can also be applied to the XQMA of block specimens and thin film specimens.